This invention relates to actuators, and more particularly to thermally sensitive actuators, for opening and closing louvre windows.
In a conventional manually openable louvre window, each of the separately pivoted louvre blades is mounted fast with a bell-crank, the free ends of the bell-cranks being pivotally coupled to a common operating member which, as the louvre blades open and close, remains parallel to the line joining the louvre blade pivot points, thus performing a parallelogram-type movement. This operating member is coupled by a pivotal link to a manually operable lever, the overall arrangement being such that, as the louvre blades move into their closed position, the mechanism behaves as an over-centre toggle to secure the louvre blades in their fully closed position.